27 Apr 2017

Shaw P et al. JAMA Psychiatry 2017; 74: 527

A commentary based on the research article by Ustun B et al. JAMA Psychiatry 2017; 74: 520-526

Diagnosis of ADHD in adults has increased over the last three decades, resulting in a current estimated prevalence of 2–5%. The Diagnostic and Statistical Manual of Mental Disorders – 5th edition (DSM-5TM) lists three important changes in adult ADHD diagnostic criteria compared with the 4th edition (DSM-IV): a reduction from six (DSM-IV) to five symptoms required for diagnosis of adult ADHD; a raised age from 7 to 12 years old for ADHD symptom onset in children; and emphasis on symptoms no longer having a “clinically significant impairment” on a patients’ day-to-day lives, but an ability to “interfere” or “lower quality”.1

A recent peer-reviewed published article by Ustun et al2 reported the first screening scale for adult ADHD using the DSM-5TM. Built using the RiskSLIM (a novel machine-learning algorithm), this model was used to offer a revised scale based on the DSM-5TM version of the World Health Organization Adult ADHD Self-Report Scale (ASRS). Six items, two of which were not connected to DSM-5TM items, were shown to provide high specificity and positive predictive value in diagnoses of adult ADHD symptoms.

Shaw et al note that inclusion of the two items not connected with the DSM-5TM (chronic procrastination and a dependence on others for maintaining order in the patient’s life) reflect executive dysfunction, and highlight that these have previously demonstrated superiority over ADHD symptoms in predicting adult ADHD. This raises the question: can current diagnostic criteria accurately detect ADHD in adults as it stands? Interestingly, the authors also noted that the prevalence of adult ADHD more than doubled from 4% to 8.2% over 10 years (by DSM-5TM standards).

Epidemiological studies have also suggested that ADHD symptoms in adults are likely to have begun in adulthood, challenging the childhood-onset model of the disorder.1

The authors concluded that, as the prevalence of adult ADHD rises, a psychometrically robust screening tool is necessary for both research purposes and identification of those who may need clinical assessment and treatment for ADHD in the future.1